Process of making cementitious products



1'06. COMPOSITIONS, 3 A

COATING R PLASTIC,

Examiner 7 (7/ also penetrate the sur ace Patented Aug. 11, 1925. H r

M Hg was 1 UNITED STATES PATENT OFFICE.

CLAUDE H. HUNSAKEB, OF ST. LOUIS, MISSOURI.

, PROCESS OF IAKING CEMENTITIOUS PRODUCTS.

Io Drawing.

To all whom it may concern:

Be it known that I, CLAUDE H. HUNSAKER, a citizen of the United States, residing at St. Louis, in the State of Missouri, have invented certain new and useful Improvements in Processes of Making Cementitious Products, of which the following is a specification.

This invention relates to the manufacture 10 of concrete or cementitious agglomerates substances such as blocks, beams and slabs employed in the construction of buildings; columns, foundations, steps and the like or other forms or shapes into which concrete or 16 cementitious substances are made.

The invention relates more particularly to a process for the treatment of the base or primary elements, such as cinders ashes clinkers s'la mine chats suc as ea an v20 ZlIlC o er Sll S 311085 use 1D 8 aggregate mixtures in manufacturing such articles, which process aims to remove or neutralize the in'urious acids alkalis or other substanfl? shill? pre'sent in H1? base and 2 in such quantities as to have an injurious efiect upon the cement used to bond the mass together. 7

It is very economical and desirable to use com aratively light substances such as ashes,

80 cin ers, clinkers and the like in the manufacture of building blocks, steps, columns, foundations and the like because of the resultant lighter weights not only in the process of manufacture, but also in freighting,

85 handling and erection or placement of the finished articles.

There is likewise a further advantage incident to the comparative porousness or lesser densities of the mass of the manufac- 40 tured articles where base aggregates of this character are used, due in part to the ease with which nails, screws and the like penetrate the articles so made and commonly used in securing the blocks, slabs and the like in secure relation to each other and to the other materials, such as boards, studdings, joists and timbers or expanded metals commonly used in the brication of buildings and structures. Cement mortar will res of such articles and will more readi bond them in fixed relation to each other.

The desirabilit of .usin ashes cinders, clinkers and the 'ke in the manufacture of such articles has been long recognized in the art, but due to the almost ever present and Application filed Kay 11, 1925. Serial No. 29,642.

varying quantities of acids, and at times alkalies, in such amounts as to have a deleterious and harmful effect upon the cement used in the manufacture of articles in which such substances are used as aggregates, such use has not been commercially acceptable.

This injurious action of these present substances which attack the cement, is more pronounced when the articles themselves are exposed to the elements, as in the outer walls of buildings, and underground where moisture and seepages from sewers and the like come into contact with the concrete or cementitious articles. It is well known that certain acids in sewage, pipes and conduits, and seepage of like substances, unite with certain acids in the aggregate and produce very harmful and injurious results, notably disintegration.

I have found in the practice of my invention that injurious or harmful quantities of acids or sul hur are usually present in cin- Hei s, ashes, c in ers and the like residuum resultant from the combustion of coal and other bituminous substances, but that the quantity and identity of such acids "aries where different bituminous products are burned, and even vary with the same product where the combustion occurs in different furnaces or under other varying conditions.

I have also found injurious quantities of acids, sulphur and alkalies present in lead mine and other chats, which destroy their value as a base in cementitious usage.

I am aware that eiforts have been made heretofore, to reduce the injurious and harmful quantities of acids, or alkalies present in cinders, ashes, clinkers, chats and the like by washing with water. Elforts along this line, however, have been of no practical value or benefit because at most such method of treatment couldonlv dilute or remove a part of the free acids or alkaparticle thereof, where such acids are at all present. It is, therefore, evident that treatments 'by washing with water are of little or no practical value, since superficial removal only is thereby possible.

By the practice of my lDYBDtlOIl all these conditions are overcome and the injurious elements are completely remoyed or neutralized, as will readily appear from the following description:

I first take samples of the ashes. cinders slam chats clinkers or other substances dcsireil to be used in the manufacture of concrete or cementitious articles and by chemical analysis determine what acid or acids, alkali or alkaline sulphur or other injurious substance is present therein, and in what combinations and quantities. I then determine the quantity of and the proper neutralizin a ent required for a given quan l y o" mce to be treated, to completely neutralize and overcome the objectionable and injurious action of the substance presenttherein.

It will be understood that the neutralizing 5 agent must be one of sufiicient qualities, quantity and active powers, that when brought into contact and thoroughly intermixed with the mass to be acted upon, to thoroughly and completely penetrate each of the particles of the mass treated and combine with or attack and neutralize the injurious substance in all the intermolecular spaces of each and every particle thereof. As an example of the practice of my in- 23 vention, by analysis or other suitable method it is found that the resultant cinder or clinker from the combustion of a certain coal contains sulphurous or sulphuric acids.

The amount or extent of such acidity is then determined, and a neutralizin a ent nch as sodium carbonate. sodium hydroxide otassium hyglfiyfie 1n the proper quanetermined acidity, is brought into contact with the mass to be treated. If on the other hand the aggregate base is found to have an alkaline condition,

acid can be employed to correct suc 1 conman.

It may be found in instances where two or more distinct acids or other injurious substances are present in any given mass, that more than one treatment of the same neutralizing agent, or separate treatments of diiierent neutralizing agents are required, the present invention residing in the remoral of any content, determined by analysis both as to character and quantity whether acid or alkali, or otherwise, which is deleterious to cement in the manufactured cementitious products of all characters.

The term aggregate base as employed is intended to comprehend any base, whether cindeis. ashes, clinkers, slag, mine chats, etc.

'hat I claim is:

1. The herein described process of making cementitious products, which consists in initially taking an aggregate base and chemieally analyzing same to determine the presence of acid or alkali elements injurious to cement both as to the nature and quantity of such elements, then in chemically treating the base to neutralize such elements, then in combining the base with cement and ater to form a plastic composition and imally moulding such composition.

2. The herein described process of making ceinentitious products, which consists in initially taking an aggregate base composed of cinders and chemically analyzing same to determine the presence of acid or alkali elements injurious to cement both as to the nature and quantity of such elements, then in chemically treating the base to neutralize such elements, then in combining the base with cement and water to form a plastic composition and finally moulding such composition.

In testimony whereof I afiix my signature.

CLAUDE H. HUNSAKER. 

